FR3024591A1 - METHOD FOR MANUFACTURING A PHOTOVOLTAIC PANEL - Google Patents

Abstract

Method for manufacturing photovoltaic panels (1) characterized in that this method consists of the following steps: depositing a metal pattern (4) on a printed circuit board (2); At least one layer of resist varnish (6) is applied to said card (2) leaving at least one varnish free area (7, 11); All or part of said so-called resist layer (6) is applied to a first mask (12) made of a polymer film; All or part of said first mask (12) is applied to a second mask (14) also constituted by a polymer film delimiting at least all or part of an implantation frame (15) of a photovoltaic cell (5); At least one photovoltaic cell (5) is deposited in said implantation frame (15) by matching at least one connection zone (8, 8a) defined under said photovoltaic cell (5) with at least one connection zone (8). , 8a) on said metal circuit (4); At least one junction tongue (16) extending between a connection zone (8, 8b) on said metal pattern (4) and a connection zone (17) on said photovoltaic cell (5) is deposited; A binding operation is performed.

Description

The invention relates to a method of manufacturing a photovoltaic panel, as well as the panel resulting from this method. The present invention is in the field of producing electrical energy by converting solar radiation. It relates more particularly to the manufacture of photovoltaic panels also called photovoltaic solar cells or modules. Such panels or sensors are direct current electrical generators consisting of a set of photovoltaic cells interconnected electrically and inserted in a sealed compartment. These panels serve as basic modules for photovoltaic installations connected or not to a public distribution network. They can deliver electricity continuously or store it on an accumulator or a capacitor. Photovoltaic cells consist of semiconductors, mainly based on silicon and, more rarely, on other semiconductors: copper selenide and indium selenide, cadmium telluride, and the like. The silicon used for the cells is produced in the form of bars. These bars are then sawn into thin plates, generally 200 micrometers thick and are usually called in the technical field considered, "wafers". Moreover, in the remainder of the description, for ease of understanding, this term will be used systematically to designate these thin plates based on silicon. After a treatment to enrich in doping elements (P, As, Sb or B), one thus obtains semiconductor silicon of P or N type. The wafers are then "metallized". Metal ribbons are embedded on each of the surfaces of these wafers and connected to electrical contacts. Once metallized, wafers have become photovoltaic cells. The different cells are distinguished according to the quality of the silicon, ie monocrystalline, polycrystalline, amorphous or of the technology used, ie in tandem, organic, polymers, multifunction or CIGS. The dimensions of the most common cells for this type of panel are standardized, because manufactured on a very large scale, generally 156 x 156 mm. Therefore, it is either necessary to adapt them or to design new ones for the manufacture of photovoltaic panels meeting particular needs. The main disadvantage of custom photovoltaic cell design is the high cost of such production. The second solution consists in cutting the standard cells to desired dimensions, for example using the technology identified under the registered trademark Laser Micro Jet® 15 developed by Synova. These cells, in general, are very fragile and must be protected from mechanical damage and moisture. The next step in production is the assembly of the cells by electrical connections in parallel or in series according to the desired intensity or voltage. Everything is arranged on a plate and installed in a waterproof frame. In particular cases where the solar panels are smaller in size, it may be necessary to trap the cells in a gelatinous liquid polymer to secure them within the thus-produced panel. This step is done manually and thus represents a cost of additional important specialized labor. Thus, the industrial production of such panels requires investments and very significant costs. The object of the present invention is to remedy these drawbacks by proposing an industrial manufacturing method which allows an alternative to the solutions implemented hitherto. Thus, the present invention aims to overcome the disadvantages of the state of the art, by proposing a method of manufacturing photovoltaic panels which consists of the following steps: - depositing a metal pattern on a printed circuit board; - Apply at least one layer of varnish savings on said card leaving at least one free area varnish; - On all or part of said said varnish layer spares a first mask consisting of a polymer film; - All or part of said first mask is applied to a second mask also consisting of a polymer film delimiting at least all or part of a setting frame of a photovoltaic cell; At least one photovoltaic cell is deposited in said implantation frame by matching at least one connection zone defined under said photovoltaic cell with at least one connection zone on said metal circuit; - At least one junction tongue extending between a connection zone on said metal pattern and a connection zone on a photovoltaic cell is deposited; - We perform a binding operation.

The advantages of the present invention are that the manufacturing process can be implemented on an automated manufacturing line without manual intervention. This results in a lower manufacturing cost and improved reliability of result. Moreover, this method according to the invention makes it possible to obtain a photovoltaic panel whose cells are perfectly positioned and immobilized, avoiding any risk of stressing these cells without it being necessary to use a filler-filling polymer. Advantageously, said savings varnish leaves free a particular space along said metal pattern. Preferably, said protective lacquer covers a transverse zone of said metallic pattern.

According to one embodiment, said varnish has a thickness equal to or less than said first mask. According to another embodiment, said first mask has a thickness equal to or less than said second mask. Advantageously, a binder compound or binding material 10 is applied to a part of said metal pattern. According to yet another embodiment, said binding operation is soldering. Preferably, said cell is deposited on both a solder cream and on said first mask. According to yet another embodiment, said first mask is made of polyamide. Advantageously, the photovoltaic panel comprises: a printed circuit board with a metallic pattern; a layer of varnish sparing on said card leaving at least one free area of varnish; - A first mask consisting of a polymer film disposed on all or part of said layer of varnish savings; a second mask also consisting of a polymer film delimiting at least all or part of an implantation frame of a photovoltaic cell disposed on all or part of said first mask; at least one photovoltaic cell disposed in the implantation frame of the second mask matching at least one connection zone defined under the photovoltaic cell with at least one connection zone on the circuit or metal pattern; a splicing tab extending between a connection area on the metallic pattern and a connection area on a photovoltaic cell; a plate or cover sheet of translucent or transparent material; peripheral sealing means. Other features and advantages of the invention will emerge from the following detailed description of non-limiting embodiments of the invention, with reference to the appended figures, in which: FIG. 1 schematically represents a view from above of FIG. a solar panel or face exposed to light radiation, according to the invention; - Figure 2 shows schematically in perspective and bursting of a photovoltaic panel according to a first embodiment; FIG. 3 is a view similar to FIG. 2, but corresponding to a second embodiment; FIG. 4 is a representation in longitudinal section of a photovoltaic panel according to the first embodiment of FIG. 2; - Figure 5 schematically shows a side view 20 in section and longitudinal assembly of a photovoltaic panel according to another embodiment; - Figure 6 schematically shows a top view of a detail of the assembly of a photovoltaic panel; Figure 7 is a longitudinal sectional view of the same detail of the assembly of a photovoltaic panel as Figure 6; - Figure 8 schematically shows a top view of the assembly of a photovoltaic panel; FIG. 9 schematically represents a cross-sectional view of a photovoltaic panel during manufacture before the binding operation; - Figure 10 is a view similar to Figure 9 after bonding. As shown in the various figures of the accompanying drawings, the present invention relates to a photovoltaic panel also called photovoltaic solar cell or module. In particular, the invention relates to a method of manufacturing such a photovoltaic panel 1.

Thus, and as illustrated in FIGS. 1 to 5, this photovoltaic panel 1 comprises a printed circuit board 2 on the upper face 3 of which at least a metallic pattern 4 is produced intended to contribute to the electrical connection of one or several photovoltaic cells 5.

The metal pattern 4 may be made of copper, an alloy comprising copper or any other metal or alloy of metals. Preferably, the cells 5 are polycrystalline photovoltaic cells sawed by Laser Micro Jet®. This division makes it possible to obtain small cells with a low short-circuit rate. Other sawing or cutting techniques can also be used for the invention of this process. It is also noted that the invention makes it possible to use cell types having different silicon quality or different technology. These cells can be connected in parallel and / or in series according to the desired intensity or voltage. It is also possible to establish a connection between each cell to have access to as much voltage level and to obtain several output connections.

This printed circuit board 2 may be a card generally used in the field of electronics as support for a circuit. However, and preferably, this circuit board 2 is made of a waterproof material.

According to the invention, and as visible in FIGS. 6, 7, 9 and 10, there is applied on this face 3 of the circuit board 2, at least one layer of varnish savings 6 leaving at least one free zone of 7. Such a zone 7 is, for example, likely to constitute a connection zone 8 of a photovoltaic cell 5 on this printed circuit board 2 as will be described further on.

Advantageously, this layer of resist varnish 6 is of thickness 9 substantially equal to the thickness 10 of the metal pattern 4. It should also be noted that on both sides of the connection zones 8 on the metallic pattern 4, spaces 11 can be preserved by the varnish savings 6 whose use will appear further in the description. According to the invention, all or part of this layer of savings lacquer 6 is applied to a first mask 12 advantageously constituted of a polymer film on which is intended to rest, at least in part, a photovoltaic cell 5 In this regard, on this first mask 12 is disposed a second mask 14 also in the form of a polymer film 15 delimiting at least all or part of an implantation frame 15 for such a photovoltaic cell 5. Very substantially and such as visible in FIG. 8, this second mask 14 defines a plurality of implantation frames 15, each being able to receive a photovoltaic cell 5 of appropriate dimensions. Through this second mask 14, these photovoltaic cells 5 are perfectly positioned above the printed circuit board 2, in particular above the connection zones 8 through which said photovoltaic cells 5 must be connected. electrically on this printed circuit board 2, more particularly, on the metal pattern 4. The implantation frames 15 are similar to reception cradles for the cells and thus avoid the phenomenon of "butterfly wings" when the cells 5 are fixed on the circuit board 2. The vertical position of the cells 5 is thus finely adjusted, the latter rest flat. It should be noted that said connection zones 8 actually break up into first connection zones 8a at which this connection of the photovoltaic cells 5 on the printed circuit board 2 and second connection areas 8b are more particularly achieved. the connection between junction tongues 16 extending between the metal pattern 4 and a connection zone 17 on a photovoltaic cell 5.

Accordingly, a step of the method according to the invention consists in depositing such a junction tongue 17 between a connection zone 8b on the metal pattern 4 and a connection zone 17 on a photovoltaic cell 5. Preferably, on the ground 4, a flux-flow barrier 18 delimits the different connection zones 8a, 8b, on the metallic pattern 4. Advantageously, these flow-flow barriers 18 or transverse zones are produced during the application. The use of these barriers 18 will appear further in the description. Note also that, according to the invention, on the connection areas 8a, 8b and 17 on a photovoltaic cell 5 is deposited a bonding material 19 for example consisting of solder paste or equivalent. In particular, on the connection zones 8a, this binding material 19 is deposited before the photovoltaic cells are deposited in their respective implantation frame 15. Likewise, on the connection zones 8b and 17, this material of FIG. binding 19 or binder compound is deposited before the establishment of a junction tongue 16. In a subsequent operation of the process according to the invention, the actual bonding is carried out which results in the application of photovoltaic cells 5 on the first mask 12 which, as shown in FIG. 10, is of thickness 13 compensating for that 20 of the bonding material 19. This bonding step of the process of the invention is preferably carried out by soldering and the material binding 19 is a solder paste. A solder (in conventional mode) according to a method known to those skilled in the art, a bonding using an electrically conductive material, a fixing of another order allowing an electrical connection or more simply a contacting are also possible in the context of the method of the invention. This brazing paste is generally composed in volume of 50% flux 190 and 50% of brazing metal alloy. The stream 190 is a fluidizing and stripping liquid, part of which evaporates during brazing and another part separates from the metal alloy. The metal alloy is generally composed inter alia of copper and / or silver and / or other metals or metal alloys.

Finally, the brazing process is carried out by thermal transfer and / or mechanical pressure. The heat transfer can be performed in a conduction mode, convection mode, radiation mode or a combination of these modes of transfer. During this process, a part of the flow 190 is deposited in the longitudinal spaces or zones 11 and a metal link is thus created between the cell 5, the pattern 4 and the joining tongue 16. When a brazing is carried out, the The metal link retracts upon cooling and presses the cell 5 into its cradle thereby resulting in increased reliability over time. As can also be seen in FIG. 10, the second mask 14 has a thickness 21 at least equal to it that is preferentially greater than that of the thickness 22 of a photovoltaic cell 5. As a result of this binding operation, it is applied on the photovoltaic panel 1 a plate or a cover film 23 in translucent material, preferably transparent. Thus, this plate 23 may be made of a mineral material such as glass or any other transparent or translucent synthetic material. In the context of a covering film 230, it may consist of ethylene vinyl acetate, EVA, or any other polymer or copolymer having light ray transparency properties. Similarly, any other material transparent to light radiation may be envisaged, for example quartz, for the purpose of for example obtaining a device sensitive to ultraviolet radiation, corundum, etc. The peripheral sealing 24 completes this photovoltaic panel 1. In the case of a cover plate 23, such peripheral sealing means 24 may consist of a seal made of a suitable material, for example a butyl seal. In the context of a covering film, it may, by peripheral welding, constitute these sealing means 24. According to another feature of the invention, on at least one of the end fields 25 of the printed circuit board 2 are defined connection terminals 26, 27 in electrical connection with the electrical pattern 4 and allowing the electrical connection of the photovoltaic panel 1 thus constituted. Advantageously, the printed circuit board 2 can accommodate all or part of the electronics necessary for the proper functioning of the photovoltaic panel 1.

Although the invention has been described with respect to a particular embodiment, it is understood that it is in no way limited thereto and that various modifications of shapes, materials and combinations thereof can be made. these various elements, without departing from the scope and spirit of the invention.

Claims (11)

REVENDICATIONS1. Method for manufacturing photovoltaic panels (1) characterized in that this method consists of the following steps: depositing a metal pattern (4) on a printed circuit board (2); At least one layer of resist varnish (6) is applied to said card (2) leaving at least one free varnish area (7, 11); All or part of said so-called resist layer (6) is applied to a first mask (12) made of a polymer film; All or part of said first mask (12) is applied to a second mask (14) also constituted by a polymer film delimiting at least all or part of an implantation frame (15) of a photovoltaic cell (5) ; At least one photovoltaic cell (5) is deposited in said implantation frame (15) by matching at least one connection zone (8, 8a) defined under said photovoltaic cell (5) with at least one connection zone (5). 8, 8a) on said metal circuit (4); At least one junction tongue (16) extending between a connection zone (8, 8b) on said metal pattern (4) and a connection zone (17) is deposited on said photovoltaic cell (5); A binding operation is performed. 30 2. Method according to the main claim wherein said saving varnish (6) leaves free a space (11) along the metal pattern (4). 3. A method according to any one of the preceding claims wherein said sparing varnish (6) covers a transverse zone (18) of said metallic pattern (4). 4. Method according to any one of the claims, wherein said savings varnish (6) has a lower than said first mask (12). preceding in equal thickness or according to any of claims wherein said first mask (12) has a lower than said second mask (14). 5. A method according to any one of the preceding claims in equal thickness or 6. The preceding method in which a binder compound (19) is applied to a part of said metallic pattern (4). The method of any of the preceding claims wherein said bonding operation is a solder. The method of claim 7 wherein said cell (5) is deposited on both a solder cream and said first mask (12). 9. A method according to any one of the preceding claims wherein said first mask (12) is made of polyamide. Photovoltaic panel (5) characterized in that it comprises: a printed circuit board (2) with a metallic pattern (4); a layer of resist varnish (6) on said card (2) leaving at least one free area of varnish (7, 25 11); a first mask (12) made of a polymer film disposed on all or part of said savings varnish layer (6); a second mask (14) also consisting of a polymer film delimiting at least all or part of an implantation frame (15) of a photovoltaic cell (5) disposed on all or part of said first mask (12); at least one photovoltaic cell (5) disposed in said implantation frame (15) of said second mask (14) matching at least one connection zone (8, 8a) defined under said photovoltaic cell (5) with at least one connecting zone (8, 8a) on said metal circuit (4); a junction tongue (16) extending between a connection zone (8, 8b) on said metal pattern (4) and a connection zone (17) on a photovoltaic cell (5); a plate or cover sheet (23, 230) of translucent or transparent material; - Peripheral sealing means (24).